1. Field of the Invention
The present invention relates to a novel isolated genes which encode a protein having a biofilm formation inhibitory activity, and a method for producing L-lysine by using a bacterial strain in which the gene is inactivated.
2. Description of the Related Art
Bacteria compete with other microorganisms for nutrients while growing under various growth conditions. When the growth conditions for bacteria become unfavorable and threaten theft survival, the bacteria utilize various survival mechanisms including biofilm formation.
Biofilms are assemblages of microorganisms encased within a self-produced matrix of extracellular polymers, which functions as a cooperative consortium. Biofilms serve as protection barriers and enable bacteria to survive as communities in biofilms in inhospitable conditions such as antibiotics treatments, host immune responses, and antibacterial agents.
Reportedly, as the mass of bacteria increases, the L-lysine production yield decreases. Thus, there is a problem that L-lysine production yield depends on changes in bacterial mass.
After numerous experiments, the inventors of the present invention have succeeded in identifying a gene related to inhibition of biofilm formation in a L-lysine-producing bacterial strain. They have also found that the growth rate of the strain can be increased by the inactivation of the gene, leading to an increase in the mass of the bacteria. Unexpectedly, they have also found that the yield of L-lysine production does not decrease at all despite the increase in the bacterial mass, thereby completing the present invention.